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skysdalimit
05-14-2016, 12:49 PM
So i'm an amateur paint polisher and aspiring detailer. I work professionally as a pinstriper and do a ton of custom painting on smaller projects. I work with all the local custom paint shops and a few collision shops. I learned to polish 15 years ago from a few painters. Techniques have changed alot since then. I'm looking to take advantage of today's new products and tools to produce near flawless finishes on my projects. We get perfect results sanding by hand and polishing with foam pads. It just takes FOREVER! 27hrs in particular for a set of harley bags, rear fender, and 1 side cover. SHEESH! 65 hrs on a 73 chevy caprice ! OH MY!

Here are my constraints i'm working with to improve my times without compromising quality completely.

1) Hard Clear. I'm spraying house of kolor UC35 or USC01. based on the fingernail test, it dries hard within 1-3 days. I can leave masking tape on it for weeks without marking after that.

2) Power Sanding. DA or Air powered Blocks. I have hand sanding aggravates the carpel tunnel in both hands so i minimize it as much as possible. I'm using 3m 6" and 3" RO sanders, Flex rotary, Mirka 3" rotary air.

3) Dry Sanding. Southern California is strict about water residue draining into the street plus i like the ability to view the work as I go.

4) 1 step Polish. I am terrible about keeping pads clean so i figure a 1 step polish would help me avoid cross contamination from project to project AND help me minimize steps.

my question is on step 2). I just started with 3m purple film dry. Worked Ok, but wore out rather fast. Any suggestions on how you dry sand? Also, what sandpaper do you suggest for sanding by hand dry? 1000 and up? I'm more worried about speeding up the process than cost of material as labor is my biggest cost. What polish would you recommend? I wet sand with 3K/5K trizact to finish.

THANKS FOR ANY INPUT!!1834818349183501835118352

xtremekustomz
05-14-2016, 01:24 PM
So i'm an amateur paint polisher and aspiring detailer. I work professionally as a pinstriper and do a ton of custom painting on smaller projects. I work with all the local custom paint shops and a few collision shops. I learned to polish 15 years ago from a few painters. Techniques have changed alot since then. I'm looking to take advantage of today's new products and tools to produce near flawless finishes on my projects. We get perfect results sanding by hand and polishing with foam pads. It just takes FOREVER! 27hrs in particular for a set of harley bags, rear fender, and 1 side cover. SHEESH! 65 hrs on a 73 chevy caprice ! OH MY!

Here are my constraints i'm working with to improve my times without compromising quality completely.

1) Hard Clear. I'm spraying house of kolor UC35 or USC01. based on the fingernail test, it dries hard within 1-3 days. I can leave masking tape on it for weeks without marking after that.

2) Power Sanding. DA or Air powered Blocks. I have hand sanding aggravates the carpel tunnel in both hands so i minimize it as much as possible. I'm using 3m 6" and 3" RO sanders, Flex rotary, Mirka 3" rotary air.

3) Dry Sanding. Southern California is strict about water residue draining into the street plus i like the ability to view the work as I go.

4) 1 step Polish. I am terrible about keeping pads clean so i figure a 1 step polish would help me avoid cross contamination from project to project AND help me minimize steps.

my question is on step 2). I just started with 3m purple film dry. Worked Ok, but wore out rather fast. Any suggestions on how you dry sand? Also, what sandpaper do you suggest for sanding by hand dry? 1000 and up? I'm more worried about speeding up the process than cost of material as labor is my biggest cost. What polish would you recommend? I wet sand with 3K/5K trizact to finish.

THANKS FOR ANY INPUT!!

I have used USC01 on a few vehicles including mine. I did an initial cut with 800 on a block followed by 1000 on a block followed by 1500 da and 3000 da. Not sure how much time I had in it but less time than you have in the harley pieces I'm sure. I did all of this wet though. I would expect dry sanding would take forever. Is there a reason why you can't just fill a bucket with water and use it to sand with? Wet a rag and hold it above the area you are sanding and squeeze a little on as needed. I've been using 3D AAT compound and 3D HD Polish for everything I do for a while now. I did a can am trailer with house of kolor black and usc01 a month or two ago. I was able to get a perfect finish with the 3D AAT alone but went ahead with a polish just to see if it would make any real difference in looks. Sounds like you might want to start with a wool pad and then go to a foam pad. If scratches are heavy I will use wool then move to an orange foam pad followed up with a blue polishing pad. I need to try it but I think I could probably go from the wool to the blue foam.

Len
05-14-2016, 01:45 PM
We rarely dry sand before buffing, it takes too long. I can use one small bucket of water for my paper and blocks and a one quart pump sprayer to wet the surface I'm sanding and those two containers will last several jobs. No puddles or water running out of the shop.

I should also add that when sanding a complete vehicle that about 75% or more of the surface is sanded using a RO sander and wet Trizact sandpaper and in that case the pump sprayer is all the water that's needed.


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ScottB
05-16-2016, 06:38 AM
I shoot flowcoats on nearly all my bikes, guns, guitars, etc. Pretty much have to since there are graphics involved. It eliminates or greatly reduces any wetsanding and buffing. If you have a nice booth, do the same with your cars. There is no magic one-step polish and pad that will produce a show finish. Change your habits and keep the pads clean.

Robert
05-16-2016, 08:34 AM
I have used USC01 on a few vehicles including mine. I did an initial cut with 800 on a block followed by 1000 on a block followed by 1500 da and 3000 da. Not sure how much time I had in it but less time than you have in the harley pieces I'm sure. I did all of this wet though. I would expect dry sanding would take forever. Is there a reason why you can't just fill a bucket with water and use it to sand with? Wet a rag and hold it above the area you are sanding and squeeze a little on as needed. I've been using 3D AAT compound and 3D HD Polish for everything I do for a while now. I did a can am trailer with house of kolor black and usc01 a month or two ago. I was able to get a perfect finish with the 3D AAT alone but went ahead with a polish just to see if it would make any real difference in looks. Sounds like you might want to start with a wool pad and then go to a foam pad. If scratches are heavy I will use wool then move to an orange foam pad followed up with a blue polishing pad. I need to try it but I think I could probably go from the wool to the blue foam.

I really like the cut you get with 800 to start though I don't trust most painters to put down enough material to handle that much loss. In fact, there is only one painter who I even like to polish behind. For the most part, they make their first cut then just scuff over it and hide the deep scratches.

There are some really good and fast dry papers out there now. Dennis Schmidt can tell you all about them. The problem as I'm sure you know is pilling but they seem to have figured out how to keep the dust from sticking on at least a couple of brands.

Sanding like you do, to an honest 3000 grit scratch is the real key to a great finish - most people don't look closely enough but I'm sure when you finish and look for shined scratch you don't find any. The finish should look like it came off the gun and the sander was never there.

I'm doing a Ferrari Superamerica for Pebble Beach next month and it has some tightening, or die back, so the whole thing is going to have to be sanded again. I'm going to do it dry because it's so much easier to see when I've removed just the amount needed and nothing more. I'm also going to use a film on a medium interface pad so I mimic the orange peel. I'm not sure how much clear is on this, it looks like plenty but there's no point in being reckless on a job like that.

Have you tried Menzerna?


Robert

xtremekustomz
05-16-2016, 03:57 PM
I really like the cut you get with 800 to start though I don't trust most painters to put down enough material to handle that much loss. In fact, there is only one painter who I even like to polish behind. For the most part, they make their first cut then just scuff over it and hide the deep scratches.

There are some really good and fast dry papers out there now. Dennis Schmidt can tell you all about them. The problem as I'm sure you know is pilling but they seem to have figured out how to keep the dust from sticking on at least a couple of brands.

Sanding like you do, to an honest 3000 grit scratch is the real key to a great finish - most people don't look closely enough but I'm sure when you finish and look for shined scratch you don't find any. The finish should look like it came off the gun and the sander was never there.

I'm doing a Ferrari Superamerica for Pebble Beach next month and it has some tightening, or die back, so the whole thing is going to have to be sanded again. I'm going to do it dry because it's so much easier to see when I've removed just the amount needed and nothing more. I'm also going to use a film on a medium interface pad so I mimic the orange peel. I'm not sure how much clear is on this, it looks like plenty but there's no point in being reckless on a job like that.

Have you tried Menzerna?


Robert

I used some Menzerna years ago but it was only the Polish. I hear the FG400 (I think that is the number) is a really impressive compound. From what I understand it was designed for the european cars with the ceramic clearcoats but does a really good job on any clear. The PO85RD is supposed to be a nice polish too. When I did my truck I shot 4 coats of clear, sanded it and shot 3 or 4 coats of reduced clear as a flow coat. The booth I was using at the time was crappy and there was no way to get a really clean job out of it so I pretty much had to sand and buff. Plus I wanted to make sure everything was really smooth because it was pretty much my "advertisement" for the paint work.